Additional grain boundary strengthening in length-scale architectured copper with ultrafine and coarse domains

Xiaodong Hou, Sebastian Krauß, Benoit Merle

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2 Citations (Scopus)
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The strength of polycrystals is known to increase with decreasing grain size, known as Hall-Petch effect. However, this relationship fails to predict the strength of samples with a non-uniform distribution of grain sizes. In this study, we purposely designed and fabricated copper micropillars with a strongly bimodal microstructure: half volume consisted of a large number of ultrafine grains, while the other half was predominantly single-crystalline. Micropillar compression evidenced that bimodal samples are 35% stronger than their counterparts containing only ultrafine grains. This paradoxical finding highlights the greater strengthening potential of microstructure distribution engineering, compared to the traditional grain refinement strategy.
Original languageEnglish
Pages (from-to)55-59
Number of pages5
JournalScripta Materialia
Early online date19 Feb 2019
Publication statusPublished - May 2019



  • Bimodal grained microstructure
  • Crystal structure
  • Grain boundary strengthening
  • Hall-Petch effect
  • Mechanical property testing

ASJC Scopus subject areas

  • Materials Science(all)
  • Condensed Matter Physics
  • Mechanics of Materials
  • Mechanical Engineering
  • Metals and Alloys

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